Message split issue

I am trying scenario to implement EOIO dynamic queue. I am able to generate dynamic queue name based on some field value of input payload.

I tried following pattern

Interface 1: file sender --> Http receiver

Interface 2: Http sender - -> Idoc receiver

PFA graphical representation.

I am passing first interface payload to interface 2 and setting queue id in http receiver.

This scenario works fine.

Now I am trying to split input message in multiple messages in interface 1. I have idoc which has multiple line items, I have to split and generate separate idoc for each line item.  While transferring message from interface 1 to interface 2, instead of calling interface 2 for each splitted idoc it is generating only single message for interface 2 which has all the splitted idocs in one payload. I want to generate separate http call for each splitted Idoc.

Please help...